Therapeutic preparation.



UNITED STATES PATN OFFC MAX ENGELMANN, 0F ELBERFELD, GERMANY, ASSIGNORTO FARBENFABRIKEN VORM. FRIEDR. BAYER & C0., 0F ELBEREELD, GERMANY, ACORPORATION OF Patented Feb. 1, 1916.

GERMANY.

THERAPEUTIC PREPARATION.

1 ,170,()56 Specification of Letters Patent.

No Drawing. Application filed January 80, 1913.

T 0 all whom it may concern:

Be it known that I, MAX ENGELMANN, doctor of philosophy, chemist,citizen of the ierman Empire, residing at Elberfeld, Germany, haveinvented new and useful Improvements in Therapeutic Preparations, ofwhich the following is a specification.

My present invention concerns the production of a therapeuticallyvaluable product being clay or kaolin impregnated with a difficultlvsoluble or insoluble silver compound. The product shows a strongdisinfecting power and is non-irritant retaining the valuable propertiesof clay (bolus alba) z'. e. its bland and protective action and itsfavorable effect upon wounds on account of its drying-up properties.

In order to illustrate the new process more fully the following exampleis given. the parts being by weight :200 parts of white clay areintroduced into a solution of 120 parts of silver nitrate in 2500 partsof a 30 per cent. alcohol and are well mixed with the liquid. After partof the liquid 1s removed by filtration the resulting product is driedand powdered. Subsequently it is introduced into a highly dilutedaqueous solution of 100 parts of sodium phosphate, well stirred with thesolution, until the insoluble or diflicultly soluble silver phosphatehas been formed, whereby the particles of clay held in suspension havedeposited thereon small portions or particles of silver phosphate,removed from the liquid, dried and pulverized. The resulting claycontains from 14; to 2 per cent. of silver.

The clay or kaolin impregnated with the insoluble or difiicultly solublesilver compound (a. g. silver phosphate) is not itself physicallychanged to any appreciable degree. but nevertheless its action ismaterially altered. If kaolin or clay be used by itself it is difiicultor impossible to sterilize it and Serial No 745,175.

as a result it frequently causes bad afterefi'ects, many cases oftetanus being due to its use. Mixtures of the clay or kaolin withnitrate of silver, potassium permanganate, etc., have heretofore beenproposed, but such mixtures. while more sterile than the clay itself,are nevertheless too irritating when used in medicine. The product ofthe present invention contains the clay most intimately incorporatedwith the silver compound and intimately coated by it. This product issterile and does not cause any irritation. The clay or kaolin stillretains its absorbent power, and the disinfecting effect of theinsoluble salt precipitated on it is many times greatei than thedisinfecting effect of the same amount of the insoluble salt by itselfThe insoluble salt thus sterilizes and imprm es the clay in its actionwhile the valuabll properties of the clay are retained and the clayitself acts as a carrier for the insoluble salt and increases itstherapeutic action to a marked degree.

I claim The new product comprising clay containing silver phosphateprecipitated thereon and throughout its mass whereby said silverphosphate is deposited on and distributed over the surface of numeroussmall particles of clay and the active surface of the silver phosphatethereby greatly extended, said product retaining the bland, protectiveand drying-up properties of the clay and possessing a strongdisinfecting action, substantially as descrlbed.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

MAX ENGELMANN. [1,. s.] Witnesses:

HELEN NUFER, ALBERT NUFER.

